Sex Ed in public schools is usually oriented to heterosexual monogamy and contains little material pertinent to sexual and gender minorities. However, there are many online sources to which you can send your teens for good information.
LGBT youth tend to be sexually active at younger ages than their straight peers, often because they want to test or confirm their identity. This is not harmful, as long as they have good information on practicing safer sex and negotiating mutual consent.
Nearly 90% of LGBTQ youth have reported being bullied and feeling unsafe at school. The good news is that there are a variety of resistance strategies you can teach your child that can build their resilience and self-confidence.